manual for medical representatives

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Beschreibung:

This book has been written for welfare of new medical representatives and for those planning to start career as medical representatives. I would be great full to those who advise correction/addition/deletion.
Thanks and regards
Syed maqbool Raza
Business Unit Manager, Continental Pharmaceuticals
0321 2828367
smaqbool.raza@gmail.com

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Beschreibung:

This book has been written for welfare of new medical representatives and for those planning to start career as medical representatives. I would be great full to those who advise correction/addition/deletion.
Thanks and regards
Syed maqbool Raza
Business Unit Manager, Continental Pharmaceuticals
0321 2828367
smaqbool.raza@gmail.com

manual for medical representatives

Hochgeladen von

Beschreibung:

This book has been written for welfare of new medical representatives and for those planning to start career as medical representatives. I would be great full to those who advise correction/addition/deletion.
Thanks and regards
Syed maqbool Raza
Business Unit Manager, Continental Pharmaceuticals
0321 2828367
smaqbool.raza@gmail.com

Manual for Medical Representatives

Edge over others

Syed maqbool raza

This book is dedicated to my parents and teachers

PrefaceDear colleagues, The need of a comprehensive, yet compact manual for understanding some basics for medical representatives has been felt for a long time. This need has resulted in compilation and development of this manual. Only topics with extreme importance and mandatory knowledge have been discussed here. I recommend that all Medical representatives and those who want to be medical representative must read and understand this book to get success in this profession. For any hindrance in grasping the content, you may always contact me.

Good luck

Syed Maqbool Raza 0300 9310813 Smaqbool.raza@gmail.com

Medical KnowledgeAnatomy: Study of structure of body organs and their locations. Physiology: Study of functions performed by body organs and there correlation with each other. Pathology: Precise study and diagnosis of disease consists of: Cause/etiology, Mechanism of disease development, structural alterations of cells (Morphologic alterations) and Consequence of changes(clinical manifestations).

Cell Basic structural and functioning unit of life. Tissue A group of cells performing a particular function. Organ A group of tissues make organ. System A group of organs make system. Body A group of systems make body.Stroma Structural cells.

Parenchyma Functional cells. Body systems: Cardiovascular system . Digestive system . Endocrine system . Excretory system . Immune system . Integumentary system . Lymphatic system . Muscular system . Nervous system . Reproductive system . Respiratory system . Skeletal system. Integument: Skin Endocrine: System of glands, each secreting a specific hormone responsible for body regulation. Lymph: Interstitial fluid, enters lymph vessels by filtration then it travels to lymph nodes, helps in removal of vaste and lymph nodes help in antibody production.

CellThe cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing (except virus, which consists only from DNA/RNA covered by protein and lipids), and is often called the building block of life.

Organisms can be classified as unicellular (consisting of a single cell; including most bacteria) or multicellular (including plants and animals). Humans contain about 10 trillion (1013) cells. Most plant and animal cells are between 1 and 100 m and therefore are visible only under the microscope. The cell was discovered by Robert Hooke in 1665. The word cell comes from the Latin cella, meaning "small room".

AnatomyThere are two types of cells: eukaryotic and prokaryotic. Prokaryotic cells are usually independent, while eukaryotic cells can either exist as a single celled organism or be found in multicellular organisms.Comparison of features of prokaryotic and eukaryotic cells Prokaryotes Typical organisms Typical size bacteria, archaea ~ 15 m[6] Eukaryotes protists, fungi, plants, animals ~ 10100 m[6] (sperm cells, apart from the tail, are smaller)

RNA-/protein- coupled in synthesis cytoplasm Ribosomes 50S+30S

Cytoplasmatic highly structured by endomembranes and a very few structures structure cytoskeleton Cell movement flagella made of flagellin flagella and cilia containing microtubules; lamellipodia and filopodia containing actin one to several thousand (though some lack mitochondria) in algae and plants single cells, colonies, higher multicellular organisms with specialized cells Mitosis (fission or budding) Meiosis

The prokaryote cell is simpler, and therefore smaller, than a eukaryote cell, lacking a nucleus and most of the other organelles of eukaryotes. There are two kinds of prokaryotes: bacteria and archaea; these share a similar structure. The nuclear material of a prokaryotic cell consists of a single chromosome that is in direct contact with the cytoplasm. Here, the undefined nuclear region in the cytoplasm is called the nucleoid. A prokaryotic cell has three architectural regions:

On the outside, flagella and pili project from the cell's surface. These are structures (not present in all prokaryotes) made of proteins that facilitate movement and communication between cells. Enclosing the cell is the cell envelope generally consisting of a cell wall covering a plasma membrane though some bacteria also have a further covering layer called a capsule. The envelope gives rigidity to the cell and separates the interior of the cell from its environment, serving as a protective filter. Though most prokaryotes have a cell wall, there are exceptions such as Mycoplasma (bacteria) and Thermoplasma (archaea). The cell wall consists of peptidoglycan in bacteria, and acts as an additional barrier against exterior forces. It also prevents the cell from expanding and finally bursting (cytolysis) from osmotic pressure against a hypotonic environment. Some eukaryote cells (plant cells and fungal cells) also have a cell wall. Inside the cell is the cytoplasmic region that contains the cell genome (DNA) and ribosomes and various sorts of inclusions. A prokaryotic chromosome is usually a circular molecule (an exception is that of the bacterium Borrelia burgdorferi, which causes Lyme disease).[7] Though not forming a nucleus, the DNA is condensed in a nucleoid. Prokaryotes can carry extrachromosomal DNA elements called plasmids, which are usually circular. Plasmids enable additional functions, such as antibiotic resistance.

Eukaryotic cellsPlants, animals, fungi, slime moulds, protozoa, and algae are all eukaryotic. These cells are about 15 times wider than a typical prokaryote and can be as much as 1000 times greater in volume. The major difference between prokaryotes and eukaryotes is that eukaryotic cells contain membrane-bound compartments in which specific metabolic activities take place. Most important among these is a cell nucleus, a membrane-delineated compartment that houses the eukaryotic cell's DNA. This nucleus gives the eukaryote its name, which means "true nucleus." Other differences include:

The plasma membrane resembles that of prokaryotes in function, with minor differences in the setup. Cell walls may or may not be present.

The eukaryotic DNA is organized in one or more linear molecules, called chromosomes, which are associated with histone proteins. All chromosomal DNA is stored in the cell nucleus, separated from the cytoplasm by a membrane. Some eukaryotic organelles such as mitochondria also contain some DNA. Many eukaryotic cells are ciliated with primary cilia. Primary cilia play important roles in chemosensation, mechanosensation, and thermosensation. Cilia may thus be "viewed as sensory cellular antennae that coordinate a large number of cellular signaling pathways, sometimes coupling the signaling to ciliary motility or alternatively to cell division and differentiation." Eukaryotes can move using motile cilia or flagella. The flagella are more complex than those of prokaryotes.

Structure of a typical animal cell

MembraneThe cytoplasm of a cell is surrounded by a cell membrane or plasma membrane. The plasma membrane in plants and prokaryotes is usually covered by a cell wall. This membrane serves to separate and protect a cell from its surrounding environment and is made mostly from a double layer of lipids (hydrophobic fat-like molecules) and hydrophilic phosphorus molecules. Hence, the layer is called a phospholipid bilayer, or sometimes a fluid mosaic membrane. Embedded within this membrane is a variety of protein molecules that act as channels and pumps that move different molecules into and out of the cell. The membrane is said to be 'semi-permeable', in that it can either let a substance (molecule or ion) pass through freely, pass through to a limited extent or not pass through at all.

Genetic materialTwo different kinds of genetic material exist: deoxyribonucleic acid (DNA) and ribonucleic acid (RNA). Most cells use DNA for their long-term information storage. The biological information contained in an organism is encoded in its DNA sequence. RNA is used for information transport (e.g., mRNA) and enzymatic functions (e.g., ribosomal RNA). Transfer RNA (tRNA) molecules are used to add amino acids during protein translation.

OrganellesThe human body contains many different organs, such as the heart, lung, and kidney, with each organ performing a different function. Cells also have a set of "little organs," called organelles, that are adapted and/or specialized for carrying out one or more vital functions. Both eukaryotic and prokaryotic cells have organelles but organelles in eukaryotes are generally more complex and may be membrane bound. There are several types of organelles in a cell. Some (such as the nucleus and golgi apparatus) are typically solitary, while others (such as mitochondria, peroxisomes and lysosomes) can be numerous (hundreds to thousands). The cytosol is the gelatinous fluid that fills the cell and surrounds the organelles.

Cell nucleus eukaryotes only - A cell's information center, the cell nucleus is the most conspicuous organelle found in a eukaryotic cell. It houses the cell's chromosomes, and is the place where almost all DNA replication and RNA synthesis (transcription) occur. The nucleus is spherical and separated from the cytoplasm by a double membrane called the nuclear envelope. The nuclear envelope isolates and protects a cell's DNA from various molecules that could accidentally damage its structure or interfere with its processing. During processing, DNA is transcribed, or copied into a special RNA, called messenger RNA (mRNA). This mRNA is then transported out of the nucleus, where it is translated into a specific protein molecule. The nucleolus is a specialized region within the nucleus where ribosome subunits are assembled. In prokaryotes, DNA processing takes place in the cytoplasm.

Mitochondria and Chloroplasts eukaryotes only - the power generators: Mitochondria are self-replicating organelles that occur in various numbers, shapes, and sizes in the cytoplasm of all eukaryotic cells. Mitochondria play a critical role in generating energy in the eukaryotic cell. Mitochondria generate the cell's energy by oxidative phosphorylation, using oxygen to release energy stored in cellular nutrients (typically pertaining to glucose) to generate ATP. Mitochondria multiply by splitting in two. Respiration occurs in the cell mitochondria. Chloroplasts can only be found in plants and algae, and they capture the sun's energy to make ATP.

Endoplasmic reticulum eukaryotes only: The endoplasmic reticulum (ER) is the transport network for molecules targeted for certain modifications and specific destinations, as compared to molecules that float freely in the cytoplasm. Golgi apparatus eukaryotes only : The primary function of the Golgi apparatus is to process and package the macromolecules such as proteins and lipids that are synthesized by the cell. Ribosomes: The ribosome is a large complex of RNA and protein molecules. They each consist of two subunits, and act as an assembly line where RNA from the nucleus is used to synthesise proteins from amino acids. Ribosomes can be found either floating freely or bound to a membrane (the rough endoplasmatic reticulum in eukaryotes, or the cell membrane in prokaryotes). Lysosomes and Peroxisomes eukaryotes only: Lysosomes contain digestive enzymes (acid hydrolases). They digest excess or worn-out organelles, food particles, and engulfed viruses or bacteria.

Centrosome the cytoskeleton organiser: The centrosome produces the microtubules of a cell a key component of the cytoskeleton. It directs the transport through the ER and the Golgi apparatus.

Vacuoles: Vacuoles store food and waste. Some vacuoles store extra water. They are often described as liquid filled space and are surrounded by a membrane. Structures outside the cell membrane

Cell wall

Many types of prokaryotic and eukaryotic cell have a cell wall. The cell wall acts to protect the cell mechanically and chemically from its environment, and is an additional layer of protection to the cell membrane. Different types of cell have cell walls made up of different materials; plant cell walls are primarily made up of pectin, fungi cell walls are made up of chitin and bacteria cell walls are made up of peptidoglycan.

Prokaryotic

CapsuleA gelatinous capsule is present in some bacteria outside the cell membrane and cell wall. The capsule may be polysaccharide as in pneumococci, meningococci or polypeptide as Bacillus anthracis or hyaluronic acid as in streptococci.Capsules are not marked by normal staining protocols and can be detected by special stain.

FlagellaFlagella are organelles for cellular mobility. The bacterial flagellum stretches from cytoplasm through the cell membrane(s) and extrudes through the cell wall. They are long and thick threadlike appendages, protein in nature. Are most commonly found in bacteria cells but are found in animal cells as well.

Fimbriae (pili)They are short and thin hair like filaments, formed of protein called pilin (antigenic). Fimbriae are responsible for attachment of bacteria to specific receptors of human cell (adherence). There are special types of pili called (sex pili) involved in conjunction.

Growth and metabolism

Between successive cell divisions, cells grow through the functioning of cellular metabolism. Cell metabolism is the process by which individual cells process nutrient molecules. Metabolism has two distinct divisions: catabolism, in which the cell breaks down complex molecules to produce energy and reducing power, and anabolism, in which the cell uses energy and reducing power to construct complex molecules and perform other biological functions. Complex sugars consumed by the organism can be broken down into a less chemically complex sugar molecule called glucose. Once inside the cell, glucose is broken down to make adenosine triphosphate (ATP), a form of energy, through two different pathways. The first pathway, glycolysis, requires no oxygen and is referred to as anaerobic metabolism. Each reaction is designed to produce some hydrogen ions that can then be used to make energy packets (ATP). In prokaryotes, glycolysis is the only method used for converting energy. The second pathway, called the Krebs cycle, or citric acid cycle, occurs inside the mitochondria and can generate enough ATP to run all the cell functions.

Self-replicationCell division involves a single cell (called a mother cell) dividing into two daughter cells. This leads to growth in multicellular organisms (the growth of tissue) and to procreation (vegetative reproduction) in unicellular organisms. Prokaryotic cells divide by binary fission. Eukaryotic cells usually undergo a process of nuclear division, called mitosis, followed by division of the cell, called cytokinesis. DNA replication, or the process of duplicating a cell's genome, always happens when a cell divides through mitosis or binary fission. In meiosis, the DNA is replicated only once, while the cell divides twice.

Protein synthesisCells are capable of synthesizing new proteins, which are essential for the modulation and maintenance of cellular activities. This process involves the formation of new protein molecules from amino acid building blocks based on information encoded in DNA/RNA. Protein synthesis generally consists of two major steps: transcription and translation. Transcription is the process where genetic information in DNA is used to produce a complementary RNA strand. This RNA strand is then processed to give messenger RNA (mRNA), which is free to migrate through the cell. mRNA molecules bind to protein-RNA complexes called ribosomes located in the cytosol, where they are translated into polypeptide sequences. The ribosome mediates the formation of a polypeptide sequence based on the mRNA sequence. The mRNA sequence directly relates to the polypeptide sequence by binding to transfer RNA (tRNA) adapter molecules in binding pockets within the ribosome. The new polypeptide then folds into a functional three-dimensional protein molecule.

DIGESTIVE SYSTEMThe gastrointestinal tract (GI tract), also called the digestive tract, or the alimentary canal, is the system of organs within multicellular animals that takes in food, digests it to extract energy and nutrients, and expels the remaining waste. The major functions of the GI tract are ingestion, digestion, absorption, and excretion. In a normal human adult male, the GI tract is approximately 6.5 meters (20 feet) long and consists of the upper and lower GI tracts. The alimentary tract of the digestive system is composed of the mouth, pharynx, esophagus, stomach, small and large intestines, rectum and anus. Associated with the alimentary tract are the following accessory organs: salivary glands, liver, gallbladder, and pancreas.

Food undergoes three types of processes in the body:

Digestion Absorption Elimination

Digestion and absorption occur in the digestive tract. After the nutrients are absorbed, they are available to all cells in the body and are utilized by the body cells in metabolism. The digestive system prepares nutrients for utilization by body cells through six activities, or functions.

IngestionThe first activity of the digestive system is to take in food through the mouth. This process, called ingestion, has to take place before anything else can happen.

Mechanical Digestion

Mechanical digestion begins in the mouth with chewing or mastication and continues with churning and mixing actions in the stomach.

Chemical DigestionThe complex molecules of carbohydrates, proteins, and fats are transformed by chemical digestion into smaller molecules (Glucose, Amino acid and Fatty acid) that can be absorbed and utilized by the cells. Chemical digestion, through a process called hydrolysis, uses water and digestive enzymes to break down the complex molecules.

MovementsAfter ingestion and mastication, the food particles move from the mouth into the pharynx, then into the esophagus. Mixing movements occur in the stomach as a result of smooth muscle contraction. These repetitive contractions usually occur in small segments of the digestive tract and mix the food particles with enzymes and other fluids. The movements that propel the food particles through the digestive tract are called peristalsis.

AbsorptionThe simple molecules that result from chemical digestion pass through cell membranes of the lining in the small intestine into the blood or lymph capillaries.This process is called absorption.

EliminationThe food molecules that cannot be digested or absorbed need to be eliminated from the body. The removal of indigestible wastes through the anus, in the form of feces, is called defecation.

Accessory organsThe salivary glands, liver, gallbladder, and pancreas are not part of the digestive tract, but they have a role in digestive activities and are considered accessory organs.

Salivary GlandsThree pairs of major salivary glands (parotid, submandibular, and sublingual glands). They secrete saliva into the oral cavity, where it is mixed with food

Cleansing action on the teeth. Moistens and lubricates food during mastication and swallowing. Dissolves certain molecules so that food can be tasted. Begins the chemical digestion of starches through the action of amylase, which breaks down polysaccharides into disaccharides.

LiverThe liver is located primarily in the right side of the body, just beneath the diaphragm. It is the largest gland in the body. On the surface, the liver is divided into two major lobes and two smaller lobes. The cells of liver are called hepatocytes. The liver receives blood from two sources. Freshly oxygenated blood is brought to the liver by the common hepatic artery, a branch of the celiac trunk from the abdominal aorta. Blood that is rich in nutrients from the digestive tract is carried to the liver by the hepatic portal vein.

Liver functions include the following:

GallbladderThe gallbladder is a pear-shaped sac that is attached to the the liver by the cystic duct. The principal function of the gallbladder is to serve as a storage reservoir for

bile. Bile is a yellowish-green fluid produced by liver cells. The main components of bile are water, bile salts, bile pigments, and cholesterol. Bile salts act as emulsifying agents in the digestion and absorption of fats. Cholesterol and bile pigments from the breakdown of hemoglobin are excreted from the body in the bile.

PancreasThe pancreas has both endocrine and exocrine functions. The endocrine portion consists of the scattered islets of Langerhans, which secrete the hormones insulin and glucagon into the blood. The exocrine portion is the major part of the gland. It consists of pancreatic acinar cells that secrete digestive enzymes into intestine. Pancreatic enzymes include anylase, trypsin, peptidase, and lipase. Pancreatic secretions are controlled by the hormones secretin and cholecystokinin.

RESPIRATORY SYSTEM

For the sake of convenience, we will divide the respiratory system in to the upper and lower respiratory tracts:

Upper Respiratory Tract

The upper respiratory tract consists of the nose and the pharynx. Its primary function is to receive the air from the external environment and filter, warm, and humidify it before it reaches the delicate lungs where gas exchange will occur. Pharynx Pharynx is a muscular tube that extends from base of the skull to its junction with esophagus. It allows air and food to pass. Part of pharynx where nasal passages open is called naso-pharynx, part where mouth opens is called oro-pharynx and part attached to larynx is called laringeopharynx. Pharynx has 7 openings: 2 from nasal passages, 1 from mouth, 1 from esophagus, 1 leading to larynx and 2 leading to middle ear. Air enters through the nostrils of the nose and is partially filtered by the nose hair, then flows into the nasal cavity. The nasal cavity is lined with epithelial tissues, containing blood vessels, which help warm the air; and secrete mucous, which further filters the

air. The endothelial lining of the nasal cavity also contains tiny hair like projections, called cilia. The cilia serve to transport dust and other foreign particles, trapped in mucous, to the back of the nasal cavity and to the pharynx, there the mucus is either coughed out, or swallowed and digested. After passing through the nasal cavity, the air flows down the pharynx to the larynx.

Lower Respiratory Tract:

The lower respiratory tract starts with the larynx, and includes the trachea, the two bronchi that branch off from the trachea, and the lungs themselves. This is where gas exchange actually takes place.

Trachea The trachea, commonly called the windpipe, is the main airway to the lungs. It divides into the right and left bronchus.

The hyaline cartilage in the tracheal wall provides support and keeps the trachea from collapsing. The

posterior soft tissue allows for expansion of the esophagus, which is immediately posterior to the trachea. The mucous membrane that lines the trachea is ciliated. Goblet cells produce mucus that trap particles and microorganisms, and the cilia propel the mucus upward, where it is either swallowed or expelled. Bronchi and Bronchial Tree Trachea divides into the right and left primary broncus. The bronchi branch into smaller and smaller passage ways (bronchioles) until they terminate in tiny air sacs called alveoli.

Lungs A pair of breathing organs, composed of spongy tissues(Alveoli), located in chest cavity Richly supplied with capillaries Brings oxygen to the blood and remove carbon dioxide

The right lung is shorter, broader, and has a greater volume than the left lung. It is divided into three lobes and each lobe is supplied by one of the secondary bronchi. The left lung is longer and narrower than the right lung. The left lung has two lobes. Each lung is enclosed by a double-layered serous membrane, called the pleura. The visceral pleura is firmly attached to the surface of the lung while parietal pleura is at outer side. The small space between the visceral and parietal pleurae is the pleural cavity. It contains a thin film of serous fluid that is produced by the pleura.

The fluid acts as a lubricant to reduce friction as the two layers slide against each other. When the respiratory system is mentioned, people generally think of breathing, but breathing is only one of the activities of the respiratory system. The body cells need a continuous supply of oxygen for the metabolic processes that are necessary to maintain life. The respiratory system works with the circulatory system to provide this oxygen and to remove the waste products of metabolism. It also helps to regulate pH of the blood. There is an exchange of gases between the lungs and the blood. This is called external respiration. The blood transports the gases to and from the tissue cells. The exchange of gases between the blood and tissue cells is internal respiration. Finally, the cells utilize the oxygen for their specific activities. This is cellular metabolism, or cellular respiration. Together these activities constitute respiration. Ventilation Ventilation, or breathing, is the movement of air through the conducting passages between the atmosphere and the lungs. The air moves through the passages because of pressure gradients that are produced by contraction of the diaphragm and thoracic muscles. Inspiration Inspiration (inhalation) is the process of taking air into the lungs. It is the active phase of ventilation because it is the result of muscle contraction. During inspiration, the diaphragm contracts and the thoracic cavity increases in volume. This decreases the intra alveolar pressure so that air flows into the lungs. Inspiration draws air into the lungs. Expiration Expiration (exhalation) is the process of letting air out of the lungs during the breathing cycle. During expiration, the relaxation of the diaphragm and elastic recoil of tissue decreases the thoracic volume and increases the intra alveolar pressure. Expiration pushes air out of the lungs.

CARDIOVASCULAR SYSTEMIt consists of the heart, which is a muscular pumping device, and a closed system of vessels called arteries, veins, and capillaries. As the

name implies, blood contained in the circulatory system is pumped by the heart which travels through the vessels.

HeartThe heart is a muscular pump that provides the force necessary to circulate the blood to all the tissues in the body. Its function is vital because, to survive, the tissues need a continuous supply of oxygen and nutrients, and metabolic waste products have to be removed.

Structure of the Heart

The human heart is a four-chambered muscular organ. The heart is enclosed in a pericardial sac that is lined with the parietal layers of a serous membrane. The visceral layer of the serous membrane forms the epicardium.

Layers of the Heart Wall

Three layers of tissue forms the heart wall. The outer layer of the heart wall is the epicardium, the middle layer is the myocardium, and the inner layer is the endocardium. Chambers of the Heart The internal cavity of the heart is divided into four chambers:o o o o

Right atrium Right ventricle Left atrium Left ventricle

The two atria are thin-walled chambers that receive blood from the veins. The two ventricles are thick-walled chambers that forcefully pump blood out of the heart. The right atrium receives deoxygenated blood from systemic veins; the left atrium receives oxygenated blood from the pulmonary veins.

Valves of the Heart Pumps need a set of valves to keep the fluid flowing in one direction and the heart is no exception. The heart has two types of valves that keep the blood flowing in the correct direction. The valves between the atria and ventricles are called atrioventricular valves (also called cuspid valves), while those at the bases of the large vessels leaving the ventricles are called semilunar valves. The right atrioventricular valve is the tricuspid valve. The left atrioventricular valve is the bicuspid, or mitral, valve. The valve between the right ventricle and pulmonary trunk is the pulmonary semilunar valve. The valve between the left ventricle and the aorta is the aortic semilunar valve. When the ventricles contract, atrioventricular valves close to prevent blood from flowing back into the atria. When the ventricles relax, semilunar valves close to prevent blood from flowing back into the ventricles.

Blood Supply to the Myocardium The myocardium of the heart wall is a working muscle that needs a continuous supply of oxygen and nutrients to function with efficiency. For this reason, cardiac muscle has an extensive network of blood vessels to bring oxygen to the contracting cells and to remove waste products. The right and left coronary arteries, (branches of the ascending aorta) supply blood to the walls of the myocardium. After blood passes through the capillaries in the myocardium, it enters a system of cardiac (coronary) veins. Most of the cardiac veins drain into the coronary sinus, which opens into the right atrium. Physiology of the Heart The work of the heart is to pump blood to the lungs through pulmonary circulation and to the rest of the body through systemic circulation. This is accomplished by systematic contraction and relaxation of the cardiac muscle in the myocardium.

Cardiac Cycle The cardiac cycle refers to the alternating contraction and relaxation of the myocardium. Systole is the contraction phase of the cardiac cycle, and diastole is the relaxation phase. At a normal heart rate, one cardiac cycle lasts for 0.8 second. Heart Sounds The sounds associated with the heartbeat are due to vibrations in the tissues and blood caused by closure of the valves. Abnormal heart sounds are called murmurs. Classification & Structure of Blood Vessels Arteries Arteries carry blood away from the heart. Pulmonary arteries transport blood (that has a low oxygen content) from the right ventricle to the

lungs. Systemic arteries transport oxygenated blood from the left ventricle to the body tissues.

Blood is pumped from the ventricles into large elastic arteries that branch repeatedly into smaller and smaller arteries until the branching results in microscopic arteries called arterioles. The arterioles play a key role in regulating blood flow into the tissue capillaries. The wall of an artery consists of three layers. The innermost layer, the tunica intima (also called tunica interna), is simple epithelium surrounded by a connective tissue basement membrane with elastic fibers. The middle layer, the tunica media, is primarily smooth muscle and is usually the thickest layer. The outermost layer, which attaches the vessel to the surrounding tissue, is the tunica externa or tunica adventitia. Capillaries Capillaries, the smallest and most numerous of the blood vessels, form the connection between the vessels that carry blood away from the heart (arteries) and the vessels that return blood to the heart (veins). The primary function of capillaries is the exchange of materials between the blood and tissue cells.

Smooth muscle cells in the arterioles where they branch to form capillaries regulate blood flow from the arterioles into the capillaries. Veins Veins carry blood toward the heart. After blood passes through the capillaries, it enters the smallest veins, called venules. From the venules, it flows into progressively larger and larger veins until it reaches the heart. In the pulmonary circuit, the pulmonary veins transport blood from the lungs to the left atrium of the heart. This blood has high oxygen content because it has just been oxygenated in the lungs. Systemic veins transport blood from the body tissue to the right atrium of the heart. This blood has reduced oxygen content because the oxygen has been used for metabolic activities in the tissue cells. The walls of veins have the same three layers as the arteries. Although all the layers are present, there is less smooth muscle and connective tissue. This makes the walls of veins thinner than those of arteries, which is related to the fact that blood in the veins has less pressure than in the arteries.

Role of the Capillaries

In addition to forming the connection between the arteries and veins, capillaries have a vital role in the exchange of gases, nutrients, and metabolic waste products between the blood and the tissue cells. Pulse and Blood Pressure Pulse refers to the rhythmic expansion of an artery that is caused by ejection of blood from the ventricle. It can be felt where an artery is close to the surface and rests on something firm. In common usage, the term blood pressure refers to arterial blood pressure, the pressure in the aorta and its branches.

Systolic pressure is due to ventricular contraction. Diastolic pressure occurs during cardiac relaxation. Pulse pressure is the difference between systolic pressure and diastolic pressure. Blood pressure is measured with a sphygmomanometer and is recorded as the systolic pressure over the diastolic pressure.

Major Systemic Arteries All systemic arteries are branches of either directly or indirectly, from the aorta. The aorta ascends from the left ventricle, curves posteriorly to the left, then descends through the thorax and abdomen. This geography divides the aorta into three portions: ascending aorta, aortic arch, and descending aorta. The descending aorta is further subdivided into the thoracic aorta and abdominal aorta. Major Systemic Veins After blood delivers oxygen to the tissues and picks up carbon dioxide, it returns to the heart through a system of veins. The capillaries, where the gaseous exchange occurs, merge into venules and these converge to form larger and larger veins until the blood reaches either the superior vena cava or inferior vena cava, which drain into the right atrium.

URINARY SYSTEM

The urinary system is the organ system that produces, stores, and eliminates urine. In humans it includes two kidneys, two ureters, the bladder, and the urethra. Functions of the Urinary System The principal function of the urinary system is to maintain the volume and composition of body fluids within normal limits. One aspect of this function is to rid the body of waste products that accumulate as a result of cellular metabolism and because of this, it is sometimes referred to as the excretory system. Although the urinary system has a major role in excretion, other organs contribute to the excretory function. The lungs in the respiratory system excrete some waste products, such as carbon dioxide and water. The skin is another excretory organ that rids the body of wastes through the sweat glands. The liver and intestines excrete bile pigments that result from the destruction of hemoglobin. The major task of excretion still belongs to the urinary system. If it fails the other organs cannot take over and compensate adequately. The urinary system maintains an appropriate fluid volume by regulating the amount of water that is excreted in the urine. Other aspects of its function include regulating the concentrations of various electrolytes in the body fluids and maintaining normal pH of the blood. In addition to maintaining fluid homeostasis in the body, the urinary system controls red blood cell production by secreting the hormone erythropoietin. The urinary system also plays a role in maintaining normal blood pressure by secreting the enzyme renin. The kidneys form the urine and account for the other functions attributed to the urinary system. The ureters carry the urine away from kidneys to the urinary bladder, which is a temporary reservoir for the urine. The urethra is a tubular structure that carries the urine from the urinary bladder to the outside. Urethra

KidneysThe kidneys are the primary organs of the urinary system. The kidneys are the organs that filter blood, remove the wastes, and excrete wastes in the urine. They are the organs that perform the functions of urinary system. The right kidney usually is slightly lower than the left because the liver displaces it downward. Each kidney is held in place by connective tissue, called renal fascia, and is surrounded by a thick layer of adipose tissue, called perirenal fat, which helps to protect it. A tough, fibrous, connective tissue renal capsule closely envelopes each kidney and provides support for the soft tissue that is inside. In the adult, each kidney is approximately 3 cm thick, 6 cm wide and 12 cm long. It is roughly bean-shaped. The outer, reddish region is the renal cortex. This surrounds a darker reddish-brown region called the renal medulla. The renal medulla consists of a series of renal pyramids, which appear striated because they contain straight tubular structures and blood vessels. The cortex (outer portion) and medulla (inner portion) make up the parenchyma, or functional tissue, of the kidney. The central region of the kidney contains the renal pelvis, which is located in the renal sinus and is continuous with the ureter. The renal pelvis is a large cavity that collects the urine as it is produced. The periphery of the renal pelvis is interrupted by cup like projections called calyces. Several minor calyces converge to form a major calyx. From the major calyces the urine flows into the renal pelvis and from there into the ureter. Each kidney contains over a million functional units, called nephrons, in the parenchyma (cortex and medulla). A nephron has two parts: a renal corpuscle and a renal tubule.The renal corpuscle consists of a cluster of capillaries, called the glomerulus, surrounded by a double-layered epithelial cup, called the glomerular(bowman) capsule. An afferent

arteriole leads into the renal corpuscle and an efferent arteriole leaves the renal corpuscle. Urine passes from the nephrons into collecting ducts then into the minor calyces.

NephronThe nephron is the functional unit of the kidney, responsible for the actual purification and filtration of the blood. About one million nephrons are in the cortex of each kidney, and each one consists of a renal corpuscle and a renal tubule which carry out the functions of the nephron.

UretersEach ureter is a small tube, about 25 cm long that carries urine from the renal pelvis to the urinary bladder.

Urinary BladderThe urinary bladder is a temporary storage reservoir for urine. The size and shape of the urinary bladder varies with the amount of urine it contains and with pressure it receives from surrounding organs. There is a triangular area, called the trigone, formed by three openings in the floor of the urinary bladder. Two of the openings are from the ureters and one of urethra.

Parietal PeritoneumThe peritoneum is a thin membrane that lines the abdominal and pelvic cavities, and covers most abdominal viscera.

UrethraThe final passageway for the flow of urine is the urethra, a thin-walled tube that conveys urine from the floor of the urinary bladder to the outside. The opening to the outside is the external urethral orifice. The internal urethral sphincter surrounds the beginning of the urethra, where it leaves the urinary bladder. In females, the urethra is short, only 3 to 4 cm (about 1.5 inches) long. The external urethral orifice opens to the outside just anterior to the opening for the vagina. In males, the urethra is much longer, about 20 cm (7 to 8 inches) in length, and transports both urine and semen. The first part, next to the urinary bladder, passes through the prostate gland and is called the prostatic urethra. The second part, a short region that penetrates the pelvic floor and enters the penis, is called the membranous urethra. The third part, the spongy urethra, is the longest region. This portion of the urethra extends the entire length of the penis, and the external urethral orifice opens to the outside at the tip of the penis

NERVOUS SYSTEMThe nervous system is the major controlling, regulatory, and communicating system in the body. It is the center of all mental activities including thought, learning, and memory.

Through its receptors, the nervous system keeps us in touch with our environment, both external and internal.

Nerve TissueAlthough the nervous system is very complex, there are only two main types of cells in nerve tissue. The actual nerve cell is the neuron. It is the "conducting" cell that transmits impulses and the structural unit of the nervous system. The other type of cell is neuroglia, or glial, cell. The word "neuroglia" means "nerve glue." These cells are nonconductive and provide a support system for the neurons. They are a special type of "connective tissue" for the nervous system.

NeuronsNeurons, or nerve cells, carry out functions of the nervous system by conducting nerve impulses. They are highly specialized and amitotic.This means that if a neuron is destroyed, it cannot be replaced because neurons do not go through mitosis.The image below illustrates the structure of a typical neuron.

Each neuron has three basic parts: cell body (soma), one or more dendrites, and a single axon.

Organization of the Nervous System The nervous system as a whole is divided into two subdivisions: the central nervous system (CNS) and the peripheral nervous system (PNS).

The Central Nervous System

The brain and spinal cord are the organs of the central nervous system. Because they are so vitally important, the brain and spinal cord, located in the dorsal body cavity, are encased in bone for protection. The brain is in the cranial vault, and the spinal cord is in the vertebral canal of the vertebral column. Although considered to be two separate organs, the brain and spinal cord are continuous at the foramen magnum. In addition to bone, the CNS is surrounded by connective tissue membranes, called meninges, and by cerebrospinal fluid.

MeningesThere are three layers of meninges around the brain and spinal cord. The outer layer, the dura mater, the middle layer of meninges is arachnoid, the pia mater is the innermost layer of meninges.

BrainThe brain is divided into the cerebrum, diencephalons, brain stem, and cerebellum.

CerebrumThe largest and most obvious portion of the brain is the cerebrum, which is divided by a deep longitudinal fissure into two cerebral hemispheres. The two hemispheres are two separate entities but are connected by an arching band of white fibers, called the corpus callosum that provides a communication pathway between the two halves. Each cerebral hemisphere is divided into five lobes, four of which have the same name as the bone over them: the frontal lobe, the parietal lobe, the occipital lobe, and the temporal lobe. A fifth lobe, the insula or Island of Reil lies deeper inside.

Diencephalon The diencephalon is centrally located and is nearly surrounded by the cerebral hemispheres. It includes the thalamus, hypothalamus, and epithalamus. The thalamus, about 80 percent of the diencephalons, consists of two oval masses of gray matter that serve as relay stations for sensory impulses, except for the sense of smell, going to the cerebral cortex. The hypothalamus is a small region below the thalamus, which plays a key role in maintaining homeostasis because it regulates many visceral activities. The epithalamus is the most dorsal portion of the diencephalons. This small gland is involved with the onset of puberty and rhythmic cycles in the body. It is like a biological clock. Brain Stem The brain stem is the region between the diencephalons and the spinal cord. It consists of three parts: midbrain, pons, and medulla oblongata. The midbrain is the most superior portion of the brain stem.

All the ascending (sensory) and descending (motor) nerve fibers connecting the brain and spinal cord pass through the medulla. Cerebellum The cerebellum, the second largest portion of the brain, is located below the occipital lobes of the cerebrum. Three paired bundles of myelinated nerve fibers,

called cerebellar peduncles, form communication pathways between the cerebellum and other parts of the central nervous system.Ventricles and Cerebrospinal Fluid

A series of interconnected, fluid-filled cavities are found within the brain. These cavities are the ventricles of the brain, and the fluid is cerebrospinal fluid (CSF). Spinal Cord The spinal cord extends from the foramen magnum at the base of the skull to the level of the first lumbar vertebra. The cord is continuous with the medulla oblongata at the foramen magnum.Like the brain, the spinal cord is surrounded by bone, meninges, and cerebrospinal fluid. The spinal cord is divided into 31 segments with each segment giving rise to a pair of spinal nerves.

The spinal cord has two main functions: Serving as a conduction pathway for impulses going to and from the brain. Sensory impulses travel to the brain on ascending tracts in the cord. Motor impulses travel on descending tracts. Serving as a reflex center. Reflexes are responses to stimuli that do not require conscious thought and consequently, they occur more quickly than reactions that require thought processes. For example, with the withdrawal reflex, the reflex action withdraws the affected part before you are aware of the pain. Many reflexes are mediated in the spinal cord without going to the higher brain centers.

The Peripheral Nervous System

The organs of the peripheral nervous system are the nerves and ganglia. Nerves are bundles of nerve fibers, much like muscles are bundles of muscle fibers. Cranial nerves and spinal nerves extend from the CNS to peripheral organs such as muscles and glands. Ganglia are collections, or small knots, of nerve cell bodies outside the CNS. The peripheral nervous system is further subdivided into an afferent (sensory) division and an efferent (motor) division. The afferent or sensory division transmits impulses from peripheral organs to the CNS. The efferent or motor division transmits impulses from the CNS out to the peripheral organs to cause an effect or action.

The peripheral nervous system consists of the nerves that branch out from the brain and spinal cord. These nerves form the communication network between the CNS and the body parts. The peripheral nervous system is further subdivided into the somatic nervous system and the autonomic nervous system. The somatic nervous system consists of nerves that go to the skin and muscles and is involved in conscious activities. The autonomic nervous system consists of nerves that connect the CNS to the visceral organs such as the heart, stomach, and intestines. It mediates unconscious activities.

Autonomic Nervous System

The autonomic nervous system is a visceral efferent system, which means it sends motor impulses to the visceral organs. The autonomic nervous system has two parts, the sympathetic division and the parasympathetic division. Many visceral organs are supplied with fibers from both divisions. In this case, one stimulates and the other inhibits. This antagonistic functional relationship serves as a balance to help maintain homeostasis.

Human nervous system

REPRODUCTIVE SYSTEMThe major function of the reproductive system is to ensure survival of the species. Other systems in the body, such as the endocrine and urinary systems, work continuously to maintain homeostasis for survival of the individual. An individual may live a long, healthy, and happy life without producing offspring, but if the species is to continue, at least some individuals must produce offspring.

Male Reproductive System

The male reproductive system consists of those organs whose function is to produce a new individual. This system consists of a pair of testes and a network of excretory ducts (epididymis, ductus deferens , vas deferens, and ejaculatory ducts, seminal vesicles), the prostate, the bulbourethral glands, and the penis.

TestesThe male gonads, testes, or testicles are covered by skin called scrotum. The scrotum consists of skin and subcutaneous tissue. A vertical septum, or partition, of subcutaneous tissue in the center divides it into two parts, each containing one testis. Each testis is an oval structure about 5 cm long and 3 cm in diameter. Testes contain leydig cells which produce spermatozoa, the process is called spermatogenesis.The spermatozoa are stored in cells called epididymis.

EpididymisSperm leave the testes through a series of efferent ducts that enter the epididymis. Each epididymis is a long (about 6 meters) tube that is tightly coiled to form a comma-shaped organ located along the superior and posterior margins of the testes. When the sperm leave the testes, they are immature and incapable of fertilizing ova. They complete their maturation process and become fertile as they move through the epididymis. Matured sperm are stored in the lower portion, or tail, of the epididymis. Ductus Deferens

The ductus deferens, also called vas deferens, is a fibromuscular tube that is continuous with the epididymis. Just before it reaches the prostate gland, each ductus deferens enlarges to form an ampulla. Sperm are stored in the proximal portion of the ductus deferens, near the epididymis, and peristaltic movements propel the sperm through the tube. Ejaculatory Duct Each ductus deferens, at the ampulla, joins the duct from the adjacent seminal vesicle to form a short ejaculatory duct. Each ejaculatory duct passes through the prostate gland and empties into the urethra.

UrethraThe urethra extends from the urinary bladder to the external urethral orifice at the tip of the penis. It is a passageway for sperm and fluids from the reproductive system and urine from the urinary system. While reproductive fluids are passing through the urethra, sphincters contract tightly to keep urine from entering the urethra.

Accessory GlandsThe accessory glands of the male reproductive system are the seminal vesicles, prostate gland, and the bulbourethral glands. These glands secrete fluids that enter the urethra. Seminal Vesicles The paired seminal vesicles are glands posterior to the urinary bladder. Each gland has a short duct that joins to form an ejaculatory duct, which then empties into the urethra. The fluid from the seminal vesicles is viscous and contains fructose, which provides an energy source for the sperm; prostaglandins, which contribute to the mobility and viability of the sperm; and proteins that cause slight coagulation reactions in the semen after ejaculation. Prostate The prostate gland is a firm, dense structure that is located just inferior to the urinary bladder. It is about the size of a walnut and encircles the urethra as it leaves the urinary bladder. Numerous short ducts from the substance of the prostate gland empty into the prostatic urethra. The secretions of the prostate (Prostatic fluid) are thin, milky colored, and alkaline. They function to enhance the motility of the sperm. Bulbourethral Glands

The paired bulbourethral glands are small, about the size of a pea, and located near the base of the penis. A short duct from each gland enters the proximal end of the penile urethra. In response to sexual stimulation, the bulbourethral glands secrete an alkaline mucus-like fluid. This fluid neutralizes the acidity of the urine residue in the urethra, helps to neutralize the acidity of the vagina, and provides some lubrication for the tip of the penis during intercourse. Seminal Fluid Seminal fluid, or semen, is a slightly alkaline mixture of sperm cells and secretions from the accessory glands. Secretions from the seminal vesicles make up about 60 percent of the volume of the semen, with most of the remainder coming from the prostate gland. The sperm and secretions from the bulbourethral gland contribute only a small volume. The volume of semen in a single ejaculation may vary from 1.5 to 6.0 ml. There are usually between 50 to 150 million spermatpzoas per milliliter of semen. Sperm counts below 10 to 20 million per milliliter usually present fertility problems. Although only one sperm actually penetrates and fertilizes the ovum, it takes several million sperm in an ejaculation to ensure that fertilization will take place.Fertilization

The process of union of two gametes whereby the somatic chromosome number is restored and the development of a new individual is initiated.

Female Reproductive System

The organs of the female reproductive system produce and sustain the female sex cells (egg cells or ova), transport these cells to a site where they may be fertilized by sperm, provide a favorable environment for the developing fetus, move the fetus to the outside at the end of the development period, and produce the female sex hormones. The female reproductive system includes the ovaries, Fallopian tubes, uterus, vagina, accessory glands, and external genital organs.

Ovaries

The primary female reproductive organs, or gonads, are the two ovaries. Each ovary is a solid, ovoid structure about the size and shape of an almond, about 3.5 cm in length, 2 cm wide, and 1 cm thick. The ovaries are located in shallow depressions, called ovarian fossae, one on each side of the uterus, in the lateral walls of the pelvic cavity. They are held loosely in place by peritoneal ligaments. Oogenesis Female sex cells, or gametes, develop in the ovaries called oogenesis. The two ovaries together contain approximately 700,000 oocytes at birth, by puberty the number of primary oocytes decline to about 400,000.

Fallopian Tubes There are two uterine tubes, also called Fallopian tubes or oviducts. There is one tube associated with each ovary allowing ovum to pass. Uterus The uterus is a muscular organ that receives the fertilized oocyte and provides an appropriate environment for the developing fetus. Before the first pregnancy, the uterus is about the size and shape of a pear, with the narrow portion directed inferiorly.

The uterus is lined with the endometrium. Vagina The vagina is a fibromuscular tube, about 10 cm long that extends from the cervix of the uterus to the outside. It is located between the rectum and the urinary bladder. The vagina serves as a passageway for menstrual flow, receives the erect penis during intercourse, and is the birth canal during childbirth.

Integumentary SystemThe integumentary system consists of the largest organ in the body, the skin. This extraordinary organ system protects the internal structures of the body from damage, prevents dehydration, stores fat and produces vitamins and hormones. It also helps to maintain homeostasis within the body by assisting in the regulation of body temperature and water balance. The integumentary system is the body's first line of defense against bacteria, viruses and other microbes. It also helps to provide protection from harmful ultraviolet radiation. The skin is a sensory organ in that it has receptors for detecting heat and cold, touch, pressure and pain. Components of the skin include hair, nails, sweat glands, oil glands, blood vessels, lymph vessels, nerves and muscles. Concerning integumentary system anatomy, the skin is composed of a layer of epithelial tissue (epidermis) that is supported by a layer of connective tissue (dermis) and an underlying subcutaneous layer (hypodermis or subcutis).

Integumentary System: Skin Layers

Epidermis - outermost layer of the skin composed of squamous cells. This layer is characterized into two distinct types: thick skin and thin skin. Dermis - thickest layer of skin that lies beneath and supports the epidermis. Hypodermis (Subcutis) - innermost layer of the skin that helps to insulate the body and cushion internal organs.

Musculoskeletal SystemThe skeletal system includes the bones of the skeleton and the cartilages, ligaments, and other connective tissue that stabilize or connect the bones. In addition to supporting the weight of the body, bones work together with muscles to maintain body position and to produce controlled, precise movements. Without the skeleton to pull against, contracting muscle fibers could not make us sit, stand, walk, or run.

Bones

There are 206 bones in the adult body. The bones of the body perform five main functions.

Provide support for the body The skeletal system provides structural support for the entire body. Individual bones or groups of bones provide a framework for the attachment of soft tissues and organs. Store minerals and lipids Calcium is the most abundant mineral in the body. (Ninety-nine percent of the body's calcium is found in the skeleton.) The calcium salts of bone are a valuable mineral reserve that maintains normal concentrations of calcium and phosphate ions in body fluids. The bones of the skeleton also store energy reserves as lipids in areas filled with yellow marrow. Produce blood cells Red blood cells, white blood cells, and other blood elements are produced in the red marrow, which fills the internal cavities of many bones. Protect body organs Many soft tissues and organs are surrounded by skeletal elements. For example, the rib cage protects the heart and lungs, the skull protects the brain, the vertebrae protect the spinal cord, and the pelvis protects the delicate reproductive organs. Provide leverage and movement Many bones function as levers that can change the magnitude and direction of the forces generated by muscles.

Bone structureEach bone in the skeleton contains two forms of tissue: compact (dense) bone that is relatively solid and spongy (cancellous) bone that forms an open network of struts and plates. Compact bone is found on the external surface of the bone. Spongy bone is located inside the bone. The proportion of compact and spongy bone varies with the shape of the bone. Compact bone is thickest where stresses arrive from a limited range of directions. Spongy bone is located where bones are not heavily stressed or where stresses arrive from many directions. Spongy bone is much lighter than compact bone, which helps reduce the weight of the skeleton and makes it easier for muscles to move the bones.

Bone development and growth

The growth of the skeleton determines the size and proportions of the body. Bones begin to form in a mother's womb about six weeks after fertilization, and portions of the skeleton do not stop growing until about the age of 25. Most bones originate as hyaline cartilage. The cartilage is gradually converted to bone through a process called ossification. Bone growth begins at the center of the cartilage. As bones enlarge, bone growth activity shifts to the ends of the bones (an area commonly called the growth plate), which results in an increase in bone length.

Bone growth "factoids"

Twenty percent of the adult skeleton is replaced each year.

Moderate amounts of physical activity and weight-bearing activities are essential to stimulate bone maintenance and to maintain adequate bone strength.

Other elements of the musculoskeletal system

Joints These are where two bones interconnect. Each joint reflects a compromise between stability and range of motion. For example, the bones of the skull are very stable but immobile, whereas the shoulder joint allows for a full range of motion but is a relatively unstable joint.

Tendons

joint

Tendons These attach muscle to bone. Ligaments These attach bone to bone. Skeletal muscles These muscles contract to pull on tendons and move the bones of the skeleton. In addition to producing skeletal movement, muscles also maintain posture and body position, support soft tissues, guard entrances and exits to the digestive and urinary tracts, and maintain body temperature. Nerves Nerves control the contraction of skeletal muscles, interprets sensory information, and coordinates the activities of the body's organ systems. Cartilage This is a type of connective tissue. It is a firm gel-like substance. The body contains three major types of cartilage: hyaline cartilage, elastic cartilage, and fibrocartilage. Hyaline cartilage is the most common type of cartilage. This type of cartilage provides stiff but somewhat flexible support. Examples in adults include the tips of ribs (where they meet the sternum) and part of the nasal septum. Another example is articular cartilage, which is cartilage that covers the ends of bones within a joint. The surfaces of articular cartilage are slick and smooth, which reduces friction during joint movement.

ligaments

Elastic cartilage provides support but can tolerate distortion without damage and return to its original shape. The external flap of the ear is one place where elastic cartilage can be found. Fibrocartilage resists compression, prevents bone-to-bone contact, and limits relative movement. Fibrocartilage can be found within the knee joint, between the pubic bones of the pelvis, and between the spinal vertebrae.

Cartilage heals poorly, and damaged fibrocartilage in joints such as the knee can interfere with normal movements. The knee contains both hyaline cartilage and fibrocartilage. The hyaline cartilage covers bony surfaces and fibrocartilage pads in the joint prevent contact between bones during movement. Injuries to the joints can produce tears in the fibrocartilage pads, and the tears do not heal. Eventually, joint mobili

IMMUNE SYSTEMThe Immune system is the bodys main defense against all foreign substances. Without the immune system, the human body would die immediately from foreign substances. As part of this more complex immune response, the vertebrate system adapts over time to recognize particular pathogens more efficiently. The adaptation process creates immunological memories and allows even more effective protection during future encounters with these pathogens. This process of acquired immunity is the basis of vaccination.

Innate Immunity It is the immunity that a body is born with and carries throughout life in its same basic form. It protects the body against the constant risk of pathogens, through the use of easily mobilized defenses that are able to recognize a wide variety of threats. The first line of defense of innate immunity is also its largest and, possibly, most important: the skin. The skin creates a physical barrier against infection by denying a pathogen contact to a host. Along with skin, the mucus (that lines the airway passages and gastrointestinal tract) also acts as a buffer, trapping foreign bodies before they are able to penetrate the system. Secondary defense includes cells known as phagocytes the most significant of which are called macrophages that attract and engulf foreign bodies so as to contain and digest them. Anti-microbial proteins may also be utilized by an immune system that is trying to contain a pathogen. And, true to its name, a complement system works in conjunction with the phagocytes by coating microbes with molecules in order to facilitate engulfment. Phagocytes that have successfully completed their work exit the body in the form of pus. Adaptive Immunity Apart from the innate immunity that a person is born with, a secondary form of immunity, known as adaptive or acquired, develops to meet the specific needs brought about by an individuals circumstances. This type of immunity constantly evolves its capacity to defend the body against pathogens. Higher vertebrates and all mammals have adaptive immunity, strengthened as a result of exposure to diseases. Vaccinations also facilitate the adaptive systems efficiency. The fundamental characteristic of adaptive immunity is that its response to a pathogen is specific and inducible: It reacts only to the specific microorganism causing an infection, and, in doing so, induces the creation of more of the antimicrobial elements necessary to eliminate the threat. Leukocytes, commonly known as white blood cells, are the dedicated agents of acquired immunity. They are found in the stem cells of a bone marrow, and, when matured, in the lymph nodes and the thymus. This improved response is then retained after the pathogen has been eliminated, in the form of an immunological memory, and allows the adaptive immune system to mount faster and stronger attacks each time this pathogen is encountered. Both innate and adaptive immunity depend on the ability of the immune system to distinguish between self and non-self molecules. In immunology, self molecules are those components of an organism's body that can be distinguished from foreign substances by the immune system. Conversely, non-self molecules are those recognized as foreign molecules. One class of non-self molecules are called

antigens (short for antibody generators) and are defined as substances that bind to specific immune receptors and elicit an immune response.

InflammationIt is immune response of body against injury or antigen, characterized by redness, swelling, pain, heat and loss of function.

Complement systemIt contains over 20 different proteins and is named for its ability to complement the killing of pathogens by antibodies. Complement is the major humoral component of the innate immune response. Leukocytes (white blood cells) act like independent, single-celled organisms and are the second arm of the innate immune system. The innate leukocytes include the phagocytes (macrophages, neutrophils, and dendritic cells), mast cells, eosinophils, basophils, and natural killer cells. These cells identify and eliminate pathogens, either by attacking larger pathogens through contact or by engulfing and then killing microorganisms. Innate cells are also important mediators in the activation of the adaptive immune system. Phagocytosis is an important feature of cellular innate immunity performed by cells called 'phagocytes' that engulf, or eat, pathogens or particles. Neutrophils and macrophages are phagocytes that travel throughout the body in pursuit of invading pathogens. Dendritic cells Dendritic cells (DC) are phagocytes in tissues that are in contact with the external environment; therefore, they are located mainly in the skin, nose, lungs, stomach, and intestines. They are named for their resemblance to neuronal dendrites, as both have many spine-like projections, but dendritic cells are in no way connected to the nervous system. Dendritic cells serve as a link between the innate and adaptive immune systems, as they present antigen to T cells, one of the key cell types of the adaptive immune system. Mast cells reside in connective tissues and mucous membranes, and regulate the inflammatory response. They are most often associated with allergy and anaphylaxis. Basophils and eosinophils are related to neutrophils. They secrete

chemical mediators that are involved in defending against parasites and play a role in allergic reactions, such as asthma. Natural killer (NK cells) cells are leukocytes that attack and destroy tumor cells, or cells that have been infected by viruses.

Adaptive immunityThe adaptive immune system evolved in early vertebrates and allows for a stronger immune response as well as immunological memory, where each pathogen is "remembered" by a signature antigen. The adaptive immune response is antigenspecific and requires the recognition of specific non-self antigens during a process called antigen presentation. Antigen specificity allows for the generation of responses that are tailored to specific pathogens or pathogen-infected cells. The ability to mount these tailored responses is maintained in the body by "memory cells". Should a pathogen infect the body more than once, these specific memory cells are used to quickly eliminate it.

LymphocytesThe cells of the adaptive immune system are special types of leukocytes, called lymphocytes. B cells and T cells are the major types of lymphocytes and are derived from hematopoietic stem cells in the bone marrow. B cells are involved in the humoral immune response, whereas T cells are involved in cell-mediated immune response. Both B cells and T cells carry receptor molecules that recognize specific targets. T cells recognize a non-self target, such as a pathogen, only after antigens (small fragments of the pathogen) have been processed and presented in combination with a self receptor called a major histocompatibility complex (MHC) molecule. There are two major subtypes of T cells: the killer T cell and the helper T cell. Killer T cells only recognize antigens coupled to Class I MHC molecules, while helper T cells only recognize antigens coupled to Class II MHC molecules. These two mechanisms of antigen presentation reflect the different roles of the two types of T cell. In contrast, the B cell antigen-specific receptor is an antibody molecule on the B cell surface, and recognizes whole pathogens without any need for antigen processing.

Killer T cellsKiller T cell are a sub-group of T cells that kill cells infected with viruses (and other pathogens), or are otherwise damaged or dysfunctional. As with B cells,

each type of T cell recognizes a different antigen. Killer T cells are activated when their T cell receptor (TCR) binds to this specific antigen in a complex with the MHC Class I receptor of another cell. Recognition of this MHC: antigen complex is aided by a co-receptor on the T cell, called CD8. The T cell then travels throughout the body in search of cells where the MHC I receptors bear this antigen. When an activated T cell contacts such cells, it releases cytotoxins that form pores in the target cell's plasma membrane, allowing ions, water and toxins to enter. This causes the target cell to undergo apoptosis. T cell killing of host cells is particularly important in preventing the replication of viruses. T cell activation is tightly controlled and generally requires a very strong MHC/antigen activation signal, or additional activation signals provided by "helper" T cells (see below).

Helper T cellsHelper T cells regulate both the innate and adaptive immune responses and help determine which types of immune responses the body will make to a particular pathogen. These cells have no cytotoxic activity and do not kill infected cells or clear pathogens directly. They instead control the immune response by directing other cells to perform these tasks. The activation of a helper T cell causes it to release cytokines that influence the activity of many cell types. Cytokine signals produced by helper T cells enhance the microbicidal function of macrophages and the activity of killer T cells.

B Lymphocytes and antibodies

A B cell identifies pathogens when antibodies on its surface bind to a specific foreign antigen. This antigen/antibody complex is taken up by the B cell and processed by proteolysis.

Passive memoryPassive immunity is usually short-term, lasting between a few days and several months. Newborn infants have no prior exposure to microbes and are particularly vulnerable to infection. Several layers of passive protection are provided by the mother. During pregnancy, a particular type of antibody, called IgG, is transported from mother to baby directly across the placenta, so human babies have high levels of antibodies even at birth, with the same range of antigen specificities as their mother. Breast milk also contains antibodies that are transferred to the gut of the infant and protect against bacterial infections until the newborn can synthesize its own antibodies. This is passive immunity because the fetus does not actually make

any memory cells or antibodies, it only borrows them. The time-course of an immune response begins with the initial pathogen encounter (or initial vaccination) and leads to the formation and maintenance of active immunological memory.

Disorders of human immunity

The immune system is a remarkably effective structure that incorporates specificity, inducibility and adaptation. Failures of host defense do occur, however, and fall into three broad categories: immunodeficiencies, autoimmunity, and hypersensitivities.

ImmunodeficienciesImmunodeficiencies occur when one or more of the components of the immune system are inactive. The ability of the immune system to respond to pathogens is diminished in both the young and the elderly, with immune responses beginning to decline at around 50 years of age. In developed countries, obesity, alcoholism, and illegal drug abuse are common causes of poor immune function. However, malnutrition is the most common cause of immunodeficiency in developing countries. Diets lacking sufficient protein are associated with impaired cell-mediated immunity, complement activity, phagocyte function, IgA antibody concentrations, and cytokine production. Deficiency of single nutrients such as zinc; selenium; iron; copper; vitamins A, C, E, and B6; and folic acid (vitamin B9) also reduces immune responses. Immunodeficiencies can also be inherited or 'acquired'. Chronic granulomatous disease, where phagocytes have a reduced ability to destroy pathogens, is an example of an inherited, or congenital, immunodeficiency. AIDS and some types of cancer cause acquired immunodeficiency.

AutoimmunityOveractive immune responses comprise the other end of immune dysfunction, particularly the autoimmune disorders. Here, the immune system fails to properly distinguish between self and non-self, and attacks part of the body. munity.

HypersensitivityHypersensitivity is an immune response that damages the body's own tissues. They are divided into four classes (Type I IV) based on the mechanisms involved and the time course of the hypersensitive reaction. Type I hypersensitivity is an immediate or anaphylactic reaction, often associated with allergy. Symptoms can range from mild discomfort to death. Type I hypersensitivity is mediated by IgE released from mast cells and basophils. Type II hypersensitivity occurs when antibodies bind to antigens on the patient's own cells, marking them for destruction. This is also called antibody-dependent (or cytotoxic) hypersensitivity, and is mediated by IgG and IgM antibodies. Immune complexes (aggregations of

antigens, complement proteins, and IgG and IgM antibodies) deposited in various tissues trigger Type III hypersensitivity reactions. Type IV hypersensitivity (also known as cell-mediated or delayed type hypersensitivity) usually takes between two and three days to develop. Type IV reactions are involved in many autoimmune and infectious diseases, but may also involve contact dermatitis . These reactions are mediated by T cells, monocytes, and macrophages.

MicrobiologyThe study of Microorganism is called Microbiology. The Main Micro Organism are

Whats Bacteria? Minute form of Microbes which is unicellular and divides by binary fission . Those Bacteria, which can cause infection, are called Pathogenic Bacteria. Bacteria which can be useful for Man are called Non Pathogenic Bacteria. Like Lactobacillus

Typical and atypical Bacteria Bacteria which can be classified by routine methods of classification are called typical bacteria while those which cannot be classified by route methods are called atypical bacteria. Atypical bacteria Are divided mainly in two groups; Cell wall defective bacteria Mycoplasma species Bacteria which survive only in WBCs Legionella Chlamydia Mycobacterium Some strains of Stah.aureus Hemophylus influenzae type-b

Motility With and Without Flagella

Spores Formation With Spores Without Spores

Gram staining method Take a sample of bacterial culture and then fix the bacteria which means drying and killing the bacteria on a glass slide Pour crystal violet and wash with running water which stain over the bacteria that turns the cell wall violet Adding the Grams Iodine solution that makes the violet color stick more firmly

Wash the glass slide with alcohol (decolorize) and some bacteria lose their color and other do not. Those retain their color (violet color) are called Gram Positive Bacteria The decolorized bacteria are stained with cefranin and become pink. These are called Gram Negative Bacteria

VirusA virus is a small infectious agent that can replicate only inside the living cells of an organism. Viruses can infect all types of organisms, from animals and plants to bacteria and archaea.[1] Virus particles (known as virions) consist of two or three parts: i) the genetic material made from either DNA or RNA, long molecules that carry genetic information; ii) a protein coat that protects these genes; and in some cases iii) an envelope of lipids that surrounds the protein coat when they are outside a cell. The shapes of viruses range from simple helical and icosahedral forms to more complex structures. The average virus is about one one-hundredth the size of the average bacterium. Most viruses are too small to be seen directly with an optical microscope. The origins of viruses in the evolutionary history of life are unclear: some may have evolved from plasmids pieces of DNA that can move between cells while others may have evolved from bacteria. In evolution, viruses are an important means of horizontal gene transfer, which increases genetic diversity.[7] Viruses are considered by some to be a life form, because they carry genetic material, reproduce, and evolve through natural selection. However they lack key characteristics (such as cell structure) that are generally considered necessary to count as life. Because they possess some but not all such qualities, viruses have been described as "organisms at the edge of life".[8] Viruses spread in many ways; viruses in plants are often transmitted from plant to plant by insects that feed on plant sap, such as aphids; viruses in animals can be carried by blood-sucking insects. These disease-bearing organisms are known as vectors. Influenza viruses are spread by coughing and sneezing. Norovirus and rotavirus, common causes of viral gastroenteritis, are transmitted by the faecaloral route and are passed from person to person by contact, entering the body in food or water. HIV is one of several viruses transmitted through sexual contact and by exposure to infected blood. The range of host cells that a virus can infect is called its "host range". This can be narrow or, as when a virus is capable of infecting many species, broad.[9] Viral infections in animals provoke an immune response that usually eliminates the infecting virus. Immune responses can also be produced by vaccines, which confer an artificially acquired immunity to the specific viral infection. However, some viruses including those that cause AIDS and viral hepatitis evade these immune responses and result in chronic infections. Antibiotics have no effect on viruses, but several antiviral drugs have been developed.

ProtozoaProtozoa are a diverse group of unicellular eukaryotic organisms, many of which are motile. In general, protozoa are referred to as animal-like protists because of movement (motile). However, both protozoa and protists are paraphyletic groups (not including all genetic relatives of the group). For example, Entamoeba is more closely related to humans than to Euglena. "Protozoa" is considered an outdated classification in more formal contexts. However, the term is still used in children's education. Protozoa is sometimes considered a subkingdom. It was traditionally considered a phylum under Animalia referring to unicellular animals, with Metazoa referring to multicellular animals. Characteristics Protozoa commonly range from 10 to 52 micrometers, but can grow as large as 1 mm, and are seen easily by microscope. The largest protozoa known are the deep-sea dwelling xenophyophores, which can grow up to 20 cm in diameter. They were considered formerly to be part of the protista family. Protozoa exist throughout aqueous environments and soil, occupying a range of trophic levels.

Chagas disease Leishmaniasis Sleeping Sickness Dysentery

Fungus: Fungi

A fungus plural: fungi or funguses is a member of a large group of eukaryotic organisms that includes microorganisms such as yeasts and molds, as well as the more familiar mushrooms. These organisms are classified as a kingdom, Fungi, which are separate from plants, animals, and bacteria. One major difference is that fungal cells have cell walls that contain chitin, unlike the cell walls of plants, which contain cellulose. Genetic studies have shown that fungi are more closely related to animals than to plants. Abundant worldwide, most fungi are inconspicuous because of the small size of their structures, and their lifestyles in soil, and dead matter. They may become noticeable when fruiting, either as mushrooms or molds. Fungi perform an essential role in the decomposition of organic matter and have fundamental roles in nutrient cycling and exchange. They have long been used as a direct source of food, such as mushrooms and truffles, as a leavening agent for bread, and in fermentation of various food products, such as wine, beer, and soy sauce. Since the 1940s, fungi have been used for the production of antibiotics, and, more recently, various enzymes produced by fungi are used industrially and in detergents. Fungi are also used as biological pesticides to control weeds, plant diseases and insect pests. Many species produce bioactive compounds called mycotoxins, such as alkaloids and polyketides that are toxic to animals including humans. The fruiting structures of a few species contain psychotropic compounds and are consumed recreationally or in traditional spiritual ceremonies. Fungi can break down manufactured materials and buildings, and become significant pathogens of humans and other animals. Losses of crops due to fungal diseases (e.g. rice blast disease) or food spoilage can have a large impact on human food supplies and local economies.

PharmacologyScience or study of chemical compounds used as drug, as well as their effects

Pharmacodynamics: Mechanism of drug action in the body. Pharmacokinetics: Study of drug absorption, distribution, biotransformation and excretion. Absorption: Process of drug transfer across a layer or layers of cells. A drug may absorb completely, partially/variably or relatively unabsorbed. Distribution: The pattern or process of carrying the drug throughout different areas of the body. Biotransformation: It refers to drug metabolism (some of catabolism and anabolism) by the body. Liver is the major site for biotransformation. It involves breakdown, structure alteration and conjugation. Excretion: Elimination of drug and their metabolites from the body through urine and feces. Toxicology: Study of poisons and/or poisoning. Pharmacotherapy: Use of drugs in the treatment of disease. Chemotherapy: Killing or slowing down invading organisms without injuring the patient. Pharmacodynamics: Mechanism of drug action in the body. Pharmacokinetics: Study of drug absorption, distribution, biotransformation and excretion. Equivalence: Comparison between two drug preparations. Chemical: Active ingredients in specific quantity. Bioequivalence: Same pattern of blood & tissue levels. Therapeutic equivalence: Same therapeutic effects.

Efficacy: Degree of response, ability of a drug to give some response Adverse effect: Unwanted effect of a drug, it could be toxic or allergic Allergic: Hypersensitivity. Dose: Amount of drug given at any one time.

Dosage: How often a dose of a drug is given, and for how long? Drug-Drug interaction: If 2 or more drugs are present in the body at the same time, one may affect the other. It can be because of disease related (GI etc), Personal (Idiosyncrasy), environmental factors. MIC : Minimum inhibitory concentration Minimum concentration of drug per ml of blood required to inhibit the growth of micro organism, measured in mg/l or mcg/ml. MBC : Minimum bactericidal concentration Minimum concentration of drug per ml of blood required to kill the micro organism, measured in mg/l or mcg/ml. PAE: Post antibiotic effect Suppressive effect of antibiotic after brief exposure to bacteria, measured in hour. Bioavailability: Percentage of active administered drug available at target site for action. Peak plasma level: Time at which drug attains maximum level in the blood. Half life: Time at which peak plasma concentration is dropped to 50%. Tmax: Time at which drug achieves maximum concentration in the blood. Cmax: Maximum drug concentration in blood. Protein binding: Percentage of drug bound to plasma protein. Steady state concentration: Time at which increase in level of drug after dose administration equals decrease in level. Dosage schedules OD Omni die, Once daily BID Bis in die, Twice a day TID Ter in die, Thrice a day QID Quater in die, Four times a day

Routes of administration of medicine Systemic Topical

A topical medication is a medication that is applied to body surfaces such as the skin or mucous membranes to treat ailments

Vial Glass bottle with closure system (screw, cork, rubber stopper) Ampoule A sealed vial. A vial sealed by melting the thin top with flame. Solution Homogenous mixture of solute and a solvent. Excipients Pharmacologically inactive substance used as carrier for the active ingredients of medication. Buffering agents Weak acid or base used to maintain the acidity (pH) of a solution at a chosen value. They prevent rapid change in pH when acid or base is added to the solution.

Empiric therapy: treatment of an infection before specific culture information has been reported or obtained Prophylactic therapy: treatment with antibiotics to prevent an infection, as in intra abdominal surgery Antibiotic: Medications used to treat bacterial infections originally obtained from other micro-organisms. FDA Pregnancy Categorization: A: Controlled studies show no risk; Adequate, well controlled studies in pregnant women have failed to demonstrate risk to the fetus e.g. ferrous sulphate, Multi vitamins and zinc etc. B: No evidence of risk in human; Either animal findings show risk while human findings do not, or, if no adequate human studies have been done, animal findings are negative e.g. Penicillin and cephalosporin C: Risk cannot be ruled out Human studies are lacking, and animal studies are either positive for risk, or are lacking as well e.g. Linezolid, Allopurinol, Albendazole D: Positive evidence of risk Investigational or post marketing data show risk to the fetus e.g. Atenolol, Doxycycline, and Enalarpil Antibiotics Classes:Sulfonamides, Penicillins, Cephalosporins, Tetracyclines, Macrolides, Aminoglycosides, Quinolones, Oxazolidinone, Streptogramins, Glycopeptides Bactericidal: kill bacteria

Bacteriostatic: inhibit growth of susceptible bacteria, rather than killing them immediately; will eventually lead to bacterial death

Blood pressure The pressure exerted by circulating blood upon the walls of blood vessels, when not specified then refers to arterial pressure. Maximum- Systolic and minimum Diastolic, 120/80 mm Hg.

Catheter: A tube which can be inserted into body cavity, duct or vessel The process of catheter insertion is called catheterization Catheter allows drainage Urinary catheter(Foley), IV catheter(Cannula), Cardiac catheter,

Some very common, but useful terminologies & their impact

Communications: Transmitting, giving or exchanging of information & messages. Courtesy: Behavior which is gracious & polite. Etiquette: Congenitally acceptable or required in society. Manners: Way of doing something, mode of procedures. Polite way of social behavior.

Smile: Sincerity transmitted through a smile not only helps relax the other person but it also manages to reduce your level of stress. Remember that only confident person can give genuine smile. Hand shake: A proper hand shake sets the tone of interaction. Courteous behavior begins to be noticed by the manner hands are shook. Eye contact: Eyes transmit your good will. Cultivate your eyes to be caring and respectful and reaction would be equally positive. Tone of voice: Your tone of voice would set the tone of communications with your clients, superiors and subordinates. Body language: Your gait, movement of hands, facial expression and dress code contribute to your body language. Let your body tell others that you care for them. Chemical transmissions: How others feel about you would directly depend on your true feelings about others. Be sincere to others and you would reap rich fruits of friendship. Active listening: Win over your clients, by paying attention to what is being said to you. Telephone courtesy: Hold telephone closed to your ear, Check the quality of voice, dont be excited as heavy breathing can be heard at the other end, be calm and composed, always say AS SALAM-O-ALAIKUM while calling or receiving, dont talk fast. Office decorum: Practice all the norms of body hygiene as body odor is possibly the biggest turn off, be careful about your oral health, and if you are smoker then pay attention to bad breath & smelly hands.

Some highly useful tips

Hotel/Restaurant manners

Do not forget to tip the porter. Do not use hand towels or curtain etc to polish your shoes. If cloth needs to be ironed, ask the concierge. However at odd times you may ask to provide electric iron. Shampoo, body lotion etc provided in the toilet are for you to use and to keep, no other thing may be kept. Remember, travel light feel well. In most restaurants there is time to limit for last order, do not try to violate. Always try to order from top of the menu towards down. Always check the bill before paying

Table manners Take your seat from the left side of chair and vacate from the right side. Do sit upright. Notice the table setting for appropriate use of the cutlery. Always use fresh dining plates instead of carrying previous for refilling. Keep pitch of your voice down. Do not put your elbow on the table. While trying to reach for anything on the table, do not stretch yourself too far. Usually soups are served by the waiter. After you have finished eating, place the fork and knife parallel to each other. Eat food and drink beverages quietly and slowly. Take small bites.

Keep your lips closed while eating. Napkin may be folded neatly when you leave the table.

Toilet and Bath room manners While using western commode, clean and wipe the seat after use. Every time one must flush. Seat cover should be lowered after flush. Avoid spitting pan/Naswar etc in basins. Do not throw cigarette buds in the commode and basin. Do not dispose sanitary napkins or diapers in the commode. Use garbage basket for disposals. Do not throw the towels on the floor after using it. Do not spill water on bath room floors.

Personal grooming Take care of dandruff. Drink 12 glasses of water daily. Use tepid and not hot water to wash your hair. Keep comb/brush with you and set hair before entering the office. Try to consume 1/5th protein, 1/5th fat and 3/5th carbohydrate for good health. Be punctual. Do not offer to shake hand, unless other extend.

Brush your teeth with vigorous massage of gums and teeth, at least twice a day. Take bath , take start with hot to warm water and end at cold water. Use deodorant after drying, take care of armpits. Change under wear, vest on daily basis. Always wear polished shoes, keep a duster with you. Keep enough visiting cards with you. Cut your nails on daily basis. Ensure at least once a month hair cut. Prepare your bag, clothes etc at night instead of morning.

Growth: Percent rate(PR)

PR = Present or future value (Vpresent) Past or present value (Vpast)/past value (Vpast) X 100. Example: Sales of a representative were Rs.100,000 in 2011 and Rs.120,000 in 2012, what is percentage growth in 2012 over 2011?

Vpresent = 120,000 Vpast = 100,000 PR = ?

120,00 100,000/100,00 X 100

PR= 20% Average: Mean

=2.5 Numbers from ratio: Example: Three numbers are in ratio of 3:5:7. If there sum is 840, find the numbers. Answer: Let the numbers are 3x, 5x and 7x So, 3x+5x+7x= 840 15x=840 X=840/15 =56 Thus the numbers are: 3x56=168, 5x56=280 and 7x56=392 Ratio from numbers: Formula: Write the numbers in ratio and divide each by smallest number Example: Calculate the ration among 50,100 and 150 = 50:100:150 50/50:100/50:150/50 1:2:3 Bracket opening: Formula: First to solve the contents of bracket, than out of bracket Example: 8(6/3 + 5x2)-1 =8(2+5x2)-1 =8(2+10)-1 =8(12)-1 =96-1 =95

Retail price from trade price; T.P/0.85 Example: If T.P of a product is 510, what would be its M.R.P? =510/0.85 =600